Even with “move”, “memmove” is a heavy process.
It’s named “Move”, but not “Move”. In order to be able to copy even overlapping address, they will copy to a temporary location and then copy to the specified address.
For a while, “memcpy” will generate bugs at overlapping addresses, so “memmove” had been recommended to use.
Personally, the load was so different that I was not use it even if it was recommended.